Ama no gawa na ni nagaretaru kai arite koyoi no tsuki wa koto ni sumikeri

天の川名に流れたる甲斐ありて
今宵の月はことに澄みけり

Roma-ji: Ama no gawa na ni nagaretaru kai arite koyoi no tsuki wa koto ni sumikeri
English Translation: Since the Heaven's River
flows so famed in name above,
it is worth its fame,
for the moon on this one night
shines especially clear.
Meaning: True to the fame of the River of Heaven flowing through the sky, tonight's moon shines especially clear.
Commentary: Autumn Poems 331

Headnote continued from the preceding poem: "The fifteenth night of the eighth month"
This is the third poem in the series on the fifteenth night. Worthy of the River of Heaven, which flows through the sky true to its name, tonight's moon shines especially clear, as though the sky had been washed clean. The sky where the moon shines clear is seen as purified by the flow of the heavenly river.
Na ni nagaru joins the sense of a name spreading widely with the flowing of a river, and nagare and sumi are associated words of the River of Heaven. In 260 the River of Heaven was sung as the river of Tanabata, while here it appears as part of the clear sky of the fifteenth night.

First line, “ama no gawa”: the band of stars that looks like a river in the sky.
Second line, “na ni nagaretaru”: its name widely spread, with nagare associated with the river of the first line.
Third line, “kai arite”: to good effect, worthily.
Fourth line, “koyoi no tsuki wa”: tonight's moon, the moon of the fifteenth.
Fifth line, “koto ni sumikeri”: koto ni means especially, and sumu, to be clear, is also associated with the river; keri expresses realization.
Author: Saigyō
Source: Sankashu
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